Vat dyestuff of the benzothionaphthene series



Patented Dec. 2, 1930.

UNITE FFICE KARL TI-IIESS AND ERNST FISCHER, OF FRANK?GET-ON-THE-MAIN-IEEOCHST. GERMANY, ASSIGNORS T GENERAL ANILI'NE VJ-OR-KS, ENG, G13 NEVA? YSEK, N. Y., A CORPOR A- TION OF IDELAXVAPUE VAT DYESTUFF OF THE BENZOTHIONAPHTHENE SERIES No Drawing. Application filed January 5, 192.), Serial No. 330,610, and in Germany January 28, 1928.

The present invention relates to a vat dyestufi, more particularly it relates to a new vat dyestulf of the thioindigo series which is obtainable by condensing ,in a solvent, while heating, 5.6 benzo 7 chloro 3 oxy-l-thionaphthene with a reactive (at-derivative of 4.5- benzo-3-oXy-1-thionaphthene, for example with an ot-anile or oc-bI'OHllClG thereof. Our new dyestuif excels the hitherto known representatives of this class of dyestuffs, especially the condensation products with the isomeric 6.7-benzo-3-oxyd-thionaphthene, in the fast mess to boiling and washing. Moreover the new dyestuff is distinguished by a great dyeg power. The same dyestuff may be ob tained by condensing an lat-derivative of 5.6 benzo 7 chloro-3-oXy-l-thionaphthene with a.5-benzo-3-oxy-l-thionaphthene.

The following example illustrates our invention but is not intended to limit it thereto, the parts being by weight.

375 parts of 4L5-benzo-3-oXy-1-thionaphthene-(paradimethylamino) -u-anile are dissolved hot in about fifteen times its weight of glacial acetic acid and filtered. 235 parts of 5.6 benzo 7 chloro -3-oxy-1-thionaphthene, dissolved in the same organic solvent, are then added to the filtrate. After the mass has been boiled in the reflux apparatus for about 2 hours, while continuously stirring, the resulting dyestuff is filtered hot by suction, washed first with glacial acetic acid, then with alcohol and dried.

The dyestutf forms a reddish-brown pow der, dissolving in sulfuric acid to a blue solution and dyeing cotton from an orange-brown vat corinth-tints. The dyestuff has the following formula:

Instead of glacial acetic acid also other ore claim: As a new product, the vat dyestufi' of the following formula:

tures. Y

KARL THIESS. ERNST FISCHER. 

